The First Journey from Docker to Podman

#CNTUG #Taiwan #podman #docker

Cloud Native Taiwan User Group #23
https://www.facebook.com/groups/cloudnative.tw/
https://www.meetup.com/CloudNative-Taiwan/events/267055874/

Slide: https://docs.google.com/presentation/d/13oUI1UwJ942gNrbzk2gRMyb7m8eQlqXhQ-Tml7Ty_iE/edit?usp=sharing

Transcript

1. The First Journey
   from Docker to Podman
   Phil Huang 黃秉鈞
   SDN x Cloud Native Meetup #23 , Taiwan, Dec. 21, 2019
   

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2. # whois Phil Huang 黃秉鈞
   ● 社群斜槓 青年 青壯年 單身
   ○ SDNDS-TW
   ○ Cloud Native Taiwan User Group (CNTUG)
   ● 任職於 Red Hat Solution Architect
   ○ Ansible IT Automation
   ○ OpenShift Container Platform
   ○ Software-Defined Networking (SDN)
   ○ Network Function Virtualization (NFV)
   ● Blog
   ○ https://blog.pichuang.com.tw
   Ref: https://www.linkedin.com/in/phil-huang-09b09895/
   

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3. Specical Thanks - 天瓏書局
   Ref: https://www.tenlong.com.tw/
   

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4. Specical Thanks - HackMD
   Ref: https://hackmd.io/c/tutorials/%2Fs%2Ftutorials
   

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5. First of All, THANKS YOU, Docker!
   

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6. Ref: https://zwischenzugs.com/2019/07/27/goodbye-docker-purging-is-such-sweet-sorrow/
   

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7. Say Hello to Podman, Buildah and Skopeo
   Ref: https://www.redhat.com/en/blog/rhel-8-enables-containers-tools-software-craftsmanship-0
   https://events19.linuxfoundation.org/wp-content/uploads/2018/07/OSS-Japan-SlidesPodman-Buildah-and-Quarkus-The-Latest-in-Linux-Container
   s-Technology-.pdf
   

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8. Please READ it again
   ● Docker Registry => Container Registry
   ● Docker Images => Container Images
   ● Docker Container => OCI Container
   ● Dockerfile => Containerfile (NEW!)
   Ref: https://dwalsh.fedorapeople.org/ReplacingDockerWithPodman.pdf
   OCI: Open Container Initiative
   

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9. All Demo Code in here
   ● GitHub: https://github.com/pichuang/debug-container
   ● Quay:
   https://quay.io/repository/pichuang/debug-container?tab=info
   

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10. Q1: How to start podman journey?
    1. Prepare a Containerfile (a.k.a Dockerfile)
    2. Install packages
    yum install podman buildah skopeo -y
    3. That’s all
    

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11. Q2: How to build a container from Containerfile?
    A: build bud -t REPO/NAME:TAG
    bud = build-using-dockerfile
    

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12. Q3: How to run the container image?
    A: podman run --rm -it --name NAME REPO/NAME:TAG
    

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13. Q4: How to inspect the container image?
    A: skopeo inspect containers-storage:REPO/NAME:TAG
    

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14. Q5: How to running containers with systemd servcies?
    A1: podman generate systemd --name NAME
    or
    A2: Gist Sample <- personally prefer
    Ref: https://www.redhat.com/sysadmin/podman-shareable-systemd-services
    

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15. Q6: How to replace docker command easily?
    A1: alias docker=podman
    or
    A2: yum install podman-docker -y
    

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16. Q7: What is the missing commands in podman?
    Those Docker commands currently do not have equivalents in podman
    ● docker {network, node, plugin, secret, service, stack, swarm}
    ● docker container {update, rename}
    Ref: https://github.com/containers/libpod/blob/master/transfer.md#missing-commands-in-podman
    

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17. Q8: Does podman can have a remote API daemon?
    ● First, Podman is a daemonless container engine
    ● Varlink - a remote API for podman
    Ref: https://github.com/containers/libpod/blob/master/docs/source/markdown/podman-varlink.1.md
    Varlink: Remote API 3rd Party Services
    

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18. Q9: Support docker-compose?
    ● Alternative project: podman-compose
    Ref: https://github.com/containers/podman-compose/tree/devel/examples
    

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19. Q10: What is the next?
    Ref: https://blog.pichuang.com.tw/20190715-troubleshooting-from-container-to-any/
    

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20. Q10: What is the next?
    Ref: https://learn.openshift.com/subsystems/
    

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21. Q11: How to run a rootless container?
    ● Example - e-minguez/ocp4-upi-bm-pxeless-staticips
    Ref: https://github.com/containers/libpod/blob/master/docs/tutorials/rootless_tutorial.md
    https://indico.cern.ch/event/757415/contributions/3421994/attachments/1855302/3047064/Podman_Rootless_Containers.pdf
    

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22. References
    ● Dockerless, part 1: Which tools to replace Docker with and why 簡中
    ● 再见 Docker，是时候拥抱下一代容器工具了
    ● Podman 介紹 - Gene Workshop
    ● Hwchiu Learning Note
    ● Kyle Bai’s Blog
    ● Twitter: Scott McCarty <- Highly Recommend
    ○ https://crunchtools.com/files/2019/05/Linux-Container-Internals-2.0.pdf
    

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23. Q&A
    台上一小時，台下三日夜
    社群正向回饋，需要一起參與
    

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